Merge branch 'master' into next

[mv-sheeva.git] / fs / btrfs / crc32c.h

diff --git a/fs/btrfs/crc32c.h b/fs/btrfs/crc32c.h
index bf6c12e8573047ccc25df10d34f13561bc50087c..6e1b3de36700470eb0b9c54b27555319321f90d2 100644 (file)
--- a/fs/btrfs/crc32c.h
+++ b/fs/btrfs/crc32c.h
@@ -1,108 +1,29 @@
+/*
+ * Copyright (C) 2008 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
 #ifndef __BTRFS_CRC32C__
 #define __BTRFS_CRC32C__
-#include <asm/byteorder.h>
 #include <linux/crc32c.h>
-#include <linux/version.h>
 
-/* #define CONFIG_BTRFS_HW_SUM 1 */
-
-#ifdef CONFIG_BTRFS_HW_SUM
-#ifdef CONFIG_X86
 /*
- * Using hardware provided CRC32 instruction to accelerate the CRC32 disposal.
- * CRC32C polynomial:0x1EDC6F41(BE)/0x82F63B78(LE)
- * CRC32 is a new instruction in Intel SSE4.2, the reference can be found at:
- * http://www.intel.com/products/processor/manuals/
- * Intel(R) 64 and IA-32 Architectures Software Developer's Manual
- * Volume 2A: Instruction Set Reference, A-M
+ * this file used to do more for selecting the HW version of crc32c,
+ * perhaps it will one day again soon.
  */
-
-#include <asm/cpufeature.h>
-#include <asm/processor.h>
-
-#define X86_FEATURE_XMM4_2     (4*32+20) /* Streaming SIMD Extensions-4.2 */
-#define cpu_has_xmm4_2         boot_cpu_has(X86_FEATURE_XMM4_2)
-
-#ifdef CONFIG_X86_64
-#define REX_PRE        "0x48, "
-#define SCALE_F        8
-#else
-#define REX_PRE
-#define SCALE_F        4
-#endif
-
-static inline u32 btrfs_crc32c_le_hw_byte(u32 crc, unsigned char const *data,
-                                  size_t length)
-{
-       while (length--) {
-               __asm__ __volatile__(
-                       ".byte 0xf2, 0xf, 0x38, 0xf0, 0xf1"
-                       :"=S"(crc)
-                       :"0"(crc), "c"(*data)
-               );
-               data++;
-       }
-
-       return crc;
-}
-
-static inline u32 __pure btrfs_crc32c_le_hw(u32 crc, unsigned char const *p,
-                                    size_t len)
-{
-       unsigned int iquotient = len / SCALE_F;
-       unsigned int iremainder = len % SCALE_F;
-#ifdef CONFIG_X86_64
-       u64 *ptmp = (u64 *)p;
-#else
-       u32 *ptmp = (u32 *)p;
-#endif
-
-       while (iquotient--) {
-               __asm__ __volatile__(
-                       ".byte 0xf2, " REX_PRE "0xf, 0x38, 0xf1, 0xf1;"
-                       :"=S"(crc)
-                       :"0"(crc), "c"(*ptmp)
-               );
-               ptmp++;
-       }
-
-       if (iremainder)
-               crc = btrfs_crc32c_le_hw_byte(crc, (unsigned char *)ptmp,
-                                             iremainder);
-
-       return crc;
-}
-#endif /* CONFIG_BTRFS_HW_SUM */
-
-static inline u32 __btrfs_crc32c(u32 crc, unsigned char const *address,
-                                size_t len)
-{
-#ifdef CONFIG_BTRFS_HW_SUM
-       if (cpu_has_xmm4_2)
-               return btrfs_crc32c_le_hw(crc, address, len);
-#endif
-       return crc32c_le(crc, address, len);
-}
-
-#else
-
-#define __btrfs_crc32c(seed, data, length) crc32c(seed, data, length)
-
-#endif /* CONFIG_X86 */
-
-/**
- * implementation of crc32c_le() changed in linux-2.6.23,
- * has of v0.13 btrfs-progs is using the latest version.
- * We must workaround older implementations of crc32c_le()
- * found on older kernel versions.
- */
-#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
-#define btrfs_crc32c(seed, data, length) \
-       __cpu_to_le32( __btrfs_crc32c( __le32_to_cpu(seed), \
-                                     (unsigned char const *)data, length) )
-#else
-#define btrfs_crc32c(seed, data, length) \
-       __btrfs_crc32c(seed, (unsigned char const *)data, length)
-#endif
+#define btrfs_crc32c(seed, data, length) crc32c(seed, data, length)
 #endif